The present invention relates to a dispenser for media, particularly for fluids and preferably liquids containing at least one pharmaceutical substance.
Such dispensers for media, in which there is usually an atomized discharge of the medium, e.g. in dosed (portioned) form, are known for the application or administration of the most varied media to the most varied locations. It is in particular known to carry out an atomized discharge of the medium in the area of the nose, in order to apply medicaments to the nasal mucosa. All types of medicaments can be involved, whose pharmaceutical substances are absorbed by the body via the nasal mucosa or respiratory tracts. Over and beyond the possibility of precisely dosing the medicaments, it is also possible using such dispensers to apply medicaments, whose active substance dosage can be critical, such as e.g. opiates. Such dispensers can also be used for the administration in precisely dosed form of anti-migraine agents and similar active substance groups. However, such dispensers are also suitable for the discharge of media with active substances used in the treatment of rheumatoid arthritis. Such dispensers must be easy to grasp and operate by a user, e.g. a user suffering from rheumatoid arthritis and whose capacity to manipulate articles may in certain circumstances be limited. The dispensers must also have a simple and inexpensive construction from a minimum number of parts.
The dispenser is suitable for the discharge of media, particularly fluids, e.g. a liquid, which preferably contain a pharmaceutical active substance or agent, such as has been specified in exemplified form hereinbefore. With the dispenser the medium is discharged in at least two proportioned partial charges through the actuation of an actuating means. The actuation of the actuating means produces a relative movement between the actuating means and a housing having a dispenser discharge opening. According to the invention an elastically deformable material bridge is provided by means of which the actuating means is held on the housing. On actuating the actuating means for producing a medium discharge, the material bridge is pretensioned by deformation.
According to a further development of the invention, the relaxing of the material bridge at the end of the actuation of an actuation-opposed return stroke is produced automatically.
It is advantageous for the material bridge to be formed from at least one web which, in the relaxed state, has a curved configuration. If e.g. the web is made from a plastics material, this can be produced by a corresponding shaping during manufacture. Precurving is a simple way of producing an elastically deformable element. Particular advantage is obtained by constructions in which the at least one web is approximately arcuate in the relaxed state. It is also possible to use ellipsoidal shapes or the like. However, the virtually arcuate shape has the advantage that the deforming forces to be absorbed are uniformly distributed in the web and consequently different loads do not have to be absorbed in different areas of the web.
According to a preferred development of the invention, there are at least two webs, which are then uniformly distributed in rotationally symmetrical manner around the central axis.
At least on the end facing the housing, the webs can meet in an annular section, which is referred to as a ring section. The webs in particular project in ray-like manner from the ring section, it is advantageous for the curvature of the webs to be chosen in such a way that the webs are oriented radially in the plane of the ring. According to an advantageous development of the invention, the ring section is supported on the dispenser housing. It can in particular be undetachably connected to the housing. The undetachable connection of the ring section to the housing can e.g. be brought about by welding, bonding or some other type of fixing or also by a one-piece construction of the ring section, housing and webs. According to alternative developments it is possible for the ring section facing the housing to be detachably fixed to the housing.
It is possible to provide on the ring section a guide sleeve, which is constructed coaxially to the central axis and projects into the interior of the housing. This sleeve can on the one hand be used for fixing the ring section to the housing and on the other also to form a guide for discharge device elements which can be placed within the housing. It is in particular possible for it to influence and/or guide the path of an actuating movement of the actuating means during a discharge stroke (actuating stroke). It can in particular hold link paths, guide links and locking means or means limiting the travel of the actuating stroke.
According to a further development of the invention, the material bridge is constructed as a bellows. The bellows preferably has a coiled folding edge configuration, which leads to a spiral spring contour-like configuration of the folding edge.
According to preferred developments of the invention, the material bridge is made from a plastics material, particularly a breaking-resistant, preferably elastically deformable plastic. It is particularly advantageous for the material bridge to be made from the same material as the dispenser housing or from at least one material, which is processable with the housing material in a multicomponent injection moulding process. In the design of the material webs it must be ensured that the actuating force on producing the dispenser discharge stroke is not immoderately increased by the material bridges.
It must simultaneously be possible to produce an adequate number of load applications in the dispenser, without there being a change to the behaviour of the material webs impairing operation. In particular, the material webs must be elastically deformable to the extent required for producing a discharge stroke. Simultaneously the forces built up through the bracing action (deformation of the material webs) must be sufficiently high to ensure that a return stroke of the actuating element takes place automatically and optionally also during the return stroke locking means must be released, pressed over or travelled over.
According to a development of the invention, the storage chamber of the container used for storing the medium is constructed as a pump chamber of a thrust piston pump. The thrust piston is preferably constructed as a plug sealing the pump chamber and in the housing there is a discharge channel leading to the discharge opening serving as a piston rod. During the first actuation, the plug is perforated by the correspondingly constructed discharge channel (needle point) and in this way the connection is formed between the pump chamber and the discharge opening. Then, during the further actuation of the dispenser, action occurs on the piston in such a way that it is moved in the sense of reducing the pump chamber volume and as a result medium is discharged through the dispenser discharge opening.
According to a preferred development of the invention, the storage container is held in a sleeve, the latter being displaceably guided with respect to the control device.
It is advantageous for the dispenser to be constructed in such a way that the container with the storage chamber can be introduced through an opening into the dispenser, the opening being in particular a ring section, which is constructed on the actuating means side and whose central axis is preferably coaxial to the central axis of an external ring section. Through such an opening, which can also be coverable, it is possible to initially almost completely produce the dispenser, assemble the same and then introduce the container with the stored medium into the assembled dispenser. This is on the one hand advantageous, because then in the pharmaceutical filling company there is no need to carry out any further assembly or fitting of the dispenser and instead the filled storage containers merely have to be inserted into the dispensers. On the other hand it is possible to provide the dispenser just prior to use with a storage container with the medium to be discharged. This can e.g. be advantageous if the active substance to be discharged must be stored in cooled or refrigerated form. In this case the volume of the parts to be cooled is reduced to the container volume, because the dispenser can be separately stored. Constructions are also conceivable where the storage container can be removed again from the dispenser and using the same dispenser and new, filled containers further, clearly defined partial medium charges can be discharged. This provides a reusability of the dispenser. The latter is particularly advantageous if the stored medium does not have a long term storage stability and it is consequently desirable to discharge the medium, e.g. in two partial charges, where a new medium container is then used for the next two partial charges.
In the case of a dispenser according to the invention, it is advantageous to construct locking and/or stop means acting at least indirectly between the actuating means and the housing and which at least serve to limit an actuating stroke. For the discharge of clearly defined partial charges, it is necessary to precisely define the actuating path of an actuating stroke. This can be advantageously achieved with the corresponding locking and/or stop means, which do not necessarily act directly between the actuating means and the housing. Instead this action can also be indirectly produced, e.g. in that the storage container is held in a sleeve, the actuating means acts on the storage container or the sleeve and the locking and/or stop means are constructed to act between the housing and the sleeve. By means of locking and/or stop means at least indirectly acting between the actuating means and the housing, it is possible to oppose a return stroke of the pump chamber during the automatic return stroke of the actuating element. This is more particularly necessary if the dispenser in question has a plunger pump, whose pump chamber simultaneously acts as a storage container.
According to developments of the invention, locking means acting at least indirectly between the actuating means and the housing are provided and which must be pressed over for producing an actuating stroke of the actuating element. They can in particular be elements having nominal breaking points and which by the tearing away of the latter release the actuating stroke. This possibility must in particular be provided if it is to be ensured that an actuating force is applied, which is sufficient for completely performing an actuating stroke. The possibility of pressing over the locking means is then selected in such a way that the necessary force is also sufficient to completely pass through an actuating stroke of the actuating element and prior to the end of the actuating stroke the user no longer has time to terminate actuation prior to the complete performance of a discharge stroke.
According to an advantageous development of the invention, the material bridge serves as an actuating means. This has the advantage that only a very small number of components is required for producing the dispenser. It is advantageous if the area of the material bridge engaging on the housing is constructed as a back-stop.
In alternative constructions, it is also possible for the material bridge to be surrounded by an actuating element in the area not covered by the housing. This construction has the advantage that the function of the material bridge cannot be destroyed by external action thereon. A completely closed housing is created, in which the material bridge is enclosed.
In order to apply to the dispenser in simple manner an opposing force counteracting the actuating force and in order to make the dispenser suitable for single-handed operation, it is advantageous to construct a back-stop on the housing.